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As you know I am currently already running DD-WRT v24-sp2 (10/10/09) mini (SVN revision 13064), do I still need to go through the official Linksys firmware and the initial DD-WRT flash before actually upgrading to the build 17990??

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I just tried upgrading the firmware to the latest "dd-wrt.v24-18946_VINT_mini.bin" but FAILED to connected to the Internet though the upgrade was successful. I then tried downgrading the firmware to "dd-wrt.v24-17990_VINT_mini.bin", the same issue; continued downgrading to the previous "DD-WRT v24-sp2 (10/10/09) mini" still did not help. The WAN interface just simply could NOT obtain an automatic IP from the modem.

All upgrade and downgrade followed the 30-30-30 reset process, strictly.

As the last resort, I flashed the WRT54G v1.1 back to the latest official version from the link you provided above. It works now!

What's the possible reason of causing the strange problem? Should I continue to flash the firmware back to DD-WRT versions? Or stick on the Cisco/Linksys firmware??

Basically, comparing to the latest official version v4.21.5, what's the benefit of using DD-WRT firmware? Better performance or security, or just more features??

More features, yes... on that specific model it's mostly the Repeater and Bridge functions of wireless, since it takes a higher core rev to assign separate MAC addresses to multiple SSIDs. But there are also settings to use for long distance WiFi with high-gain directional antennae, like the Ack timing (2000m default maximum)... if you're trying to connect to a station 10 miles away, you need to be able to increase that or it gives up waiting for an Ack and resends the same packet over and over. et cetera

Theoretically, that should not affect the WAN port, but if it does then Eko should be notified... possibly he's not trying any of the builds on older routers to see if any (let alone all) features actually work right, and is relying on users to report any such problems.

But no, I can't say I've ever seen the WAN port work with the stock Linksys firmware, but not with DD-WRT firmware. Then again, mostly what I've been using them for are APs, repeaters or bridges, typically assigning the WAN port to the switch.

Yes, different hardware model, different behaviour on DD-WRT. But I would guess any individual WRT54G on specific version should have the exact same behaviour on DD-WRT. Do you mean they might be working differently?

I can't illustrate it other than to say I've taken apart Linksys WRT routers that differed in version by only 0.1 and they had totally different hardware inside them, and I've seen WRT routers of the same version that had different chips in them... it's like they buy the parts in lots, and when they run out they could be replaced by a lot from another manufacturer that is allegedly pin-for-pin compatible... but that doesn't mean they always are totally interchangeable. Most of the individual components are only 5%-10% tolerance, so a 1.1k ohm resistor spec'd on the schematic could actually be anywhere between 990 and 1210 ohms unless they've spec'd a tight tolerance part (which would be more expensive)... multiply that slight difference by dozens of components, and you could have quite a performance difference just from that.

I eventually got a chance to upgrade the firmware from Linksys 4.21.5 to DD-WRT v24-18946 NEWD/VINT Mini, both upgraded successfully but had the same issue as before: no internet connection.

Another frustrated thing was that I could not flash the firmware to NEWD Standard due to upgrade failure.

Now the most frustrated thing is, after switching back to Linksys official firmware 4.21.5, all LAN interfaces no longer work, and the WAN interface seems working as a LAN interface because all IP addresses obtained over wireless are on the WAN subnet. In other words, the WRT54G is now actually working in AP mode, all wireless clients are obtaining their IP from the modem directly.

Looks like different people have different problems with it, so unless they report having a WRT54G v1.1 it wouldn't necessarily apply to your router. You might report your problem in that thread, by the way, after you've arrived at that point again. In the first message (dated 04-07), by the way, Fractal recommends giving it an after-flash wait up to 10 minutes, instead of the 5-minutes I noted in http:#a37794994

> BTW, what does the "2123" mean here??

Not sure, but it's probably a way for their website to track whence the link originated.

What I am currently running is SVN revision 14896 - v24-sp2 Mini Generic built on 08/07/10.

So far it is stable on my WRT54G.

It seems no point for me to upgrade any more if no critical vulnerability found in this build, as you know, this kind of upgrade might be time consuming and frustrated if the hardware is incompatible or something missing in the middle. :-)

Anyway, thanks heaps for your continued help and valuable information.